Finishing tool



R. G. AMES FINISHING IOOL.

Oct. 16, 1951 Filed Sept. 23, 1947 V K? R 4 Sheets-Sheet l INVENTOR.

ROBERT (3. AMES A-r TO RN EYS Oct. 16, 1951 AMES 2,571,096

FINISHING TOOL Filed Sept. 23, 1947 Y 4 Sheets-Sheet 2 & w

H Q R JNVENTOR. NR N N 6 RoeER-r G-AMES AT TORNEYS R. G. AMES FINISHING TOOL Oct. 16, 1951 4 Sheets-Sheet 5 Filed Sept. 23, 1947 Oct. 16, 1951 R. G. AMES 257L096 FINISHING TOOL Filed Sept. 23, 1947 4 sheets sheet 4 AT TORNEYS i atenteci Oct. 16,1951

FINISHING TOOL Robert G. Ames, Burlingame, Calif., assignor of one-half to George W. Williams and onefourth to Stanley Ames, both of Burlingame,

Calif.

Application September 23, 1947, Serial No. 775,724

Claims. 1

An object of my invention is to provide a finishing tool which is an improvement over the form of pressure plastic applicator shown in my United States Letters Patent No. 2,436,783, dated March 2, 1948. In said patent I show an applicator plate for applying mastic to a joint between two sections of wall-board and this plate has an opening therein through which the mastic passes. Novel means is provided for automatically stopping the flow of mastic through the plate opening when less mastic is needed to apply to the joint than is being fed or when the operator shuts off the mastic feeding mechanism when he reaches the end of ajoint and desires to remove the device from the wall-board surface.

In the present invention a hollow casing or body is used for receiving the mastic and a portion of the body is provided with a flexible wall that will actuate means for opening a switch as soon as a predetermined quantity of mastic is received in the hollow body. The opening of the switch will disconnect the mastic feeding mechanism from a source of current and in this way the flow of mastic to the hollow body is stopped.

In a tool of this type it is advisable to provide a trailing edge that is flexible so as to be formed into the desired curvature. For example, in the application of mastic it is advisable in some instances to form the outer surface of the mastic with a crown effect and in other cases it is desirable to form the outer mastic surface with a slight concave curve. An object of the present invention is to provide novel means whereby the trailing edge can be formed into the desired shape and maintained in this shape.

The tool shows wear at the trailing edge due to the nature of the mastic used and I therefore provide a semi-flexible bar which is rectangular in shape and use means for positioning any one of the four corners of the bar to constitute a trailing edge. In this way the life of the bar is made four times as long as would be the case where only one bar corner could be used.

It is further important to providea flexible wall connection between the trailing edge bar and the body of the casing so that the bar can be flexed into different curvatures to give the proper contour to the outer surface of the mastic and still form a part of the body outlet open- Other objects andv advantages will appear in the following specification, and the novel features of the device will be particularly pointed out in the appended claims.

My invention is illustrated in the accompanying drawings forming a part of this application, in which:

Figure l is a side elevation of the tool showing it operatively connected to a mechanism that will furnish mastic to the tool under pressure;

Figure 2 is a wiring diagram;

Figure 3 is a bottom plan view of the device shown on a larger scale than that of Figure 1;

Figure 4 is a side elevation of the device shown on a larger scale than Figure 1 and illustrating the application of mastic to a vertical wall;

Figure 5 is a front elevation of Figure 4;

Figure 6 is a top plan view of the mastic applicator head shown on a larger scale than that of Figure 5;

Figure '7 is a front elevation of Figure 6;

Figure 8 is a longitudinal section taken along the line VIII-VIII of Figure 6;

Figure 9 is a transverse section taken along the line IX-IX of Figure 7 and is shown on a larger scale than that of Figure 7;

Figure 10 is an isometric view of the trailing edge bar;

Figure 11 is an isometric view of the removable bafile plate;

Figure 12 is'an isometric view of the central clip used for connecting the flexible wall with the trailing edge bar; and

Figure 13 is a similar view of one of the other clips used for the same purpose.

While I have shown only the preferred form of my invention, it should be understood that various changes or modifications may be made within the scope of the appended claims without departing from the spirit and scope of the invention.

I will first describe the mastic feeding mechanism, then the tool body construction and operating handle, then the deformable trailing bar, the automatic mastic feed control and finally the operation of the entire device. These will be taken up in the order given.

Mastic feeding mechanism In carrying out my invention, I make use of a mastic feeding mechanism indicated generally at A and this mechanism is similar to that shown in Figure 6 in my United States Patent No. 2,436,783, dated March 2, 194.8. The mechanism comprises a platform I supported by caster wheels 2 or other suitable means, and the platform carries a hopper 3 in which mastic is placed.

A gear pump 4 draws mastic from the hopper through a pipe 5 and delivers the mastic under pressure into a flexible hose 6.

bail 21.

The finishing tool comprises a body indicated generally at B in Figure 8 and this body is preferably in the form of a casting. The body has a top wall II and two end walls I2. Figure 9 shows the body B provided with a front wall l3 and a rear wall I4. It will be seen from Figure 8 that the interior of the body is hollow to form a mastic receiving compartment BI. This compartment is provided with inwardly extending projections I5 that are integral with the body and are provided with L-shaped bores I6 through which the mastic enters the body interior. The outlet ends IEa of the bores are spaced inwardly from the end walls I2 an appreciable distance so that the mastic entering the compartment BI will have substantially a uniform density throughout the entire area of the compartment.

I have found that if the outlet ends Ilia are disposed too close to the side walls I2, then the pressure of the mastic will be greater adjacent to these walls than it will be at the center of the body. Also, if the entrance of the mastic into the compartment is placed at the center then the pressure of the mastic is increased at the 7 central point with a decrease in pressure at points adjacent to the end walls. I have found that the positioning of the outlet ends at the places indicated in Figure 8 provides a more uniform pressure of mastic throughout the entire compartment.

The L-shaped bores I6 communicate with L-shaped pipes I! that have threaded portions IIa received in threaded recesses I8 provided in the upper wall I I of 'the body. The recesses communicate with the bores I6. The other ends of the L-shaped pipes H are threaded at Ill) and rotatably receive L-shaped attachments I9 that are threaded onto the threaded portions I'Ib. The attachments are free to turn on the portions I11) and have flexible hose sections 20, see Figure 6, connected thereto.

Figures 4 and 5 clearly show the L-shaped attachments I9 connected to the flexible hose sections 20 and further show the other ends of the hose sections connected to tubes 2I communicate with the interior of a hollow handle C. The outer end of the hollow handle is provided with a valve D, see Figure l, and the hose 6 connects with the valve. When the handle 22 of the valve is swung to open the valve, mastic will be fed from the hose 8 into the hollow handle C and will be guided to the interior of the body B by the hose sections '20. Figure 1 also shows the handle 22 provided with a terminal 23 and this terminal is brought into contact with a terminal '24 when the valve D is opened. The closing of the two terminals 23 and 24 will connect the motor 'to the battery 9 or to a source of current in a manner hereinafter described more fully.

The handle C has a solid portion CI that is disposed between the tubes 2I and the body '13. The portion CI is bifurcated at 25 and the two arms thus provided are pivoted at 28 to a rigid The arms 27a of the bail are pivotally connected at 28 to the end walls I2 of the body B.

that

The pivot point 28 between the bail 21 and the body B is important and this will be more fully set forth hereafter. The connection between the handle C and body B is such that the handle may be swung in the direction of the length of the body by pivoting about the pivot 26 and may be swung in the direction of the front and rear walls of the body by swinging about the pivots 28. The hose sections 20 will permit such movement without interfering with the feeding of the mastic to the interior of the body.

Figure 8 shows the end walls I2 of the body supporting side wings 29. These wings have an under edge 30, see Figure 9, that extends at an angle to the under side of the body. The edges ride on the surfaces of the wall-board sections as shown in Figure 4 and tilt the body B in its relation to the wall board surface. The purpose of the wings 29 is to provide space between the wall board surfaces and the body for the passage of mastic to the wall-board surfaces.

Figure 9 also shows a baffle plate SI that closes a portion of the compartment BI. An isometric view of the bafile plate is illustrated in Figure 11 and it will be seen that the plate has two upstanding end flanges 32 and a longitudinally extending flange 33. The plate does not close the entire compartment and it has a curved edge 3Ia, see Figures 3 and 11, and this edge controls the flow of mastic from the compartment on to the wall-board surface. Figure 9 shows the flange 33 secured to the wall I3 of the body by a plate 34. Figure 8 shows the end flanges 32 held against the end walls I2 of the body by the wings 29. The bailie is removably secured to the body and can be removed when it is desired to attach a new bafile to the body.

Deformable trailing bar One of the important features of the invention is the provision of a flexible trailing bar that will permit the application of mastic to the wallbcard surface and will give the desired contour to the outer surface of the mastic layer. The bar is shown at E in Figure 10 and it will be seen that it is rectangular in cross section and has its ends slotted at 35. The bar is co-extensive with the length of the body B and is adapted to receive a plurality of clips of the shape shown at F in Figure 13, these clips being removably secured to the bar. In Figure 7 I show four such clips disposed on each side of a central clip FI of the shape shown in Figure 12. Each clip F has a channel portion 36 for receiving the bar and a smaller channel portion 3? for receiving the edge 38 of a flexible wall 39, see Figure 9.

In like manner the central clip FI has a channel 36a for receiving the bar and a second channel 31a for receiving the edge of the flexible wall 39. The central clip also has an upstanding lug 40 with an opening 4| for pivotally receiving an adjusting rod 42, see Figure 7. The rod 42 has a pin 43 that pivotally connects the rod with the lug 40. The rod 42 is slidably received in the body B, see Figure 9, and the upper end of the rod is notched at 44 for receiving one end of a lever 45, see Figure 7. The lever 45 is fulcrumed in a recess 46 provided in a bracket 41 that in turn is mounted on the body B. The other end of the lever 45 is bifurcated at 48 and receives a screw 49, the latter being rigidly secured to the body B, see Figure 7. Knurled nuts are mounted on the screw 49 above and below the lever 45 and an adjustment of the nuts will 3 swing the lever for causing the rod 42 to flex the bar E into the desired shape.

Figure 7 illustrates one end of the bar E as having a pin 51 passing through one of the slots 35 in the bar. The pin is carried by one of the wings 29 and the wing is notched at 52 for receiving the end of the bar. The arrangement is such that the lower surface 53 of the bar has a trailing corner 53a lying flush with the lower edge 30 of the wing. The other wing 29 carries a removable pin 59, see Figure 7, and this pin is designed to enter the other notch 35 at the end of the bar. When the trailing edge 53a becomes worn and it is desired to bring one of the other three corners into a position to constitute a trailing edge, the pin 54 can be removed and this will permit the bar E to be removed from the clips F and PI and turned into a position where a new corner will be brought into a place where it will act as a trailing edge. In this way all four corners of the bar can be made to constitute trailing edges.

Automatic mastic feed control I provide novel means for opening the electric circuit to the motor when the mastic receiving compartment BI is filled with mastic. In Figures 6 to 8, inclusive, I show a lever G that is pivoted at 55 to ears 56 that are integral with the top wall II of the body B. The lever has a plate 51 riveted thereto at 58 or otherwise secured and this plate has a convex undersurface 58a that bears against a flexible wall portion 59, see Fig-- ure 9, which in'reality is a continuation of the flexible wall 39. The wall portion 59 covers an opening 60 provided in the top wall H and the plate 51 with the lever G can move down into the opening as clearly shown in Figure 9.

The flexible wall portion 59 does not extend throughout the entire length of the upper wall H and it is secured to the under surface of the wall by strips 6!, see Figure 8, and rivets 62 or other suitable fastening means. Figure 9 shows additional strips 63 and rivets 64 for securing the longitudinally extending portions of the wall to the inner surfaces of the front and rear walls 13 and M of the body.

When the mastic entering the compartment Bl completely fills the compartment, the flexible wall portion 59 will be bulged outwardly and this will tend to lift the plate 51 and with it the lever G. The free end 65 of the lever has an opening 66 for slidably receiving a screw 6'! that is carried by the body B. A coil spring 68 is mounted on the screw and bears against the free end 65 of the lever for urging the lever toward the partition 59. The tension on the spring is controlled by the adjustment of a knurled nut 69 that is mounted on the screw 61.

The lever G carries an arm ll on which an electrical terminal H3 is mounted. This terminal is insulated from the arm (see Figure 8). The arm is in the nature of a leaf spring and is riveted to the lever at 12. The arrangement is such that the flexible wall portion 59 will bulge to a predetermined extent and raise the lever G, but the leaf spring arm II will cause the terminal 19 to contact a second terminal 13 during the initial flexing of the wall portion 59. When the lever G moves to a certain point, the contacts H1 and 13 will be separated, thus breaking the motor ci cuit. The terminal 13 is carried by the body B and is insulated therefrom. A wire 14 leads from the terminal l3 and a second wire leads from the terminal 10.

It is best now to describe the wiring diagram which is shown in Figure 2. The terminals 10 and 13 just referred to are indicated in Figure 2 and the wire 15 leads from the terminal 10 and connects with the terminal 23 on the valve handle 22. A wire 16 extends from the terminal 24 to the battery 9, or other source of current. The wire 14 from the terminal 73 leads to the solenoid l0 and the solenoid is connected to the source of current by a wire Tl.

When the valve lever 22 is moved to open the valve D, the contacts 23 and 24 will be closed and inasmuch as the compartment Bl of the body B hasno mastic at the start of operations, the terminals 19 and 13 will be closed and current will therefore flow from the battery 9 or other source of current through the solenoid coil ID. The energizing of the coil will move a contact 18 of the solenoid armature into contact with another terminal 19 and this will connect the motor I with the source of current.

Operation The motor will actuate the'pump 4 and force mastic under pressure into the tool body compartment BI. As soon as the mastic reaches a point where the flexible Wall portion 59 will be moved, the terminals 10 and 13 will be separated and this will cut off the flow of current to the solenoid H) with the result that the contacts 18 and 15 will be opened and current will cease flowing to the motor. The pump will therefore stop and no further mastic will be delivered to the compartment Bl.

While the device is being used the quantity of mastic in the compartment Bl will be reduced and the spring 68 will force the lever G and the plate 51 against the flexible wall portion.59 for moving these parts and causing the terminal 10 to again contact the terminal 13. This will result in the immediate operation of the motor and the pumping of additional mastic to the body B. It will therefore be seen that the supply of mastic to the body is automatically controlled and the operator need not check to see that too great or too little a quantity of mastic is being fed to the tool. There will be no slopping over of the mastic on the wall-board sections due to an excess of mastic feed.

The tool in being moved over the wall-board sections is moved in the direction of the arrow a shown in Figure 4. This causes the trailing bar E with its corner 53a to constitute the trailing edge of the tool. The mastic is fed out through the opening provided by the curved edge 31a of the baffle 3!. The wings 29 space the body from the wall board surface except for the trailing edge and permit an appreciable amount of mastie to be applied to the two wall board sections shown at H and J in Figure 5. The mastic will cover the joint or seam formed between the sections and indicated at 89. The contour of the upper surface of the mastic when applied to the wall-board sections is controlled by the particular arcuate shape given to the trailing bar E. As already stated, the bar is flexed into either a convex or concave shape by ad usting the knurled nuts 59, see Figure 7, and these will impart movement to the rod 42 by means of lever 45 and will move the central clip F! in the desired direction. Normally a slight crown effect is provided for the mastic layer and therefore the bar E will be given a slight concave shape.

The position of the pivots 28 in connecting the handle with the body B is important. If these pivot points are too far in front of the trailing bar E, the pressure of the mud inside the compartment Bl will force against the wall-board surfaces and will tend to raise the blade off from the wall-board surface. On the other hand, if the pivot points 28 are placed too near the trailing bar E, the runners 29 or wings would have a tendency to rock about the trailing edge as a pivot to space themselves from the wall board surface. I have found that the position of the pivots as indicated is the best for an effective operation of the tool.

As already stated, the turning of the trailing bar E in four different positions prolongs the life of the bar. The single rubber member forming the flexible wall portions 39 and 59 provides a novel means for permitting the trailing bar to be flexed to the desired degree and also permitting the motor to be automatically turned on and oil according to the flow of mastic from the tool. The pressure of the mastic in the compartment can be built up to any desired extent before the motor is turned off by the mere adjustment of the knurled nut 69. The baffle 3| is removably secured to the body so in case of wear a new bafiie can be readily substituted.

Figure 1 shows the position of the tool when applied to a vertical joint on a wall indicated generally at K. The tool is moved downwardly. For the lower portion of the vertical joint, the tool could be moved upwardly. The operator can move the platform I readily over the floor L. The handle C of the tool is long enough to permit ceiling joints to be covered with mastic. The ceiling is indicated at M in Figure 1.

The baffle plate 3| may have its trailing curved edge 3hr provided with a strip of rubber, not shown, which is attached thereto. The edge SM is flexible, but the addition of the rubber strip will increase the flexibility of the edge.

I claim:

1. In a finishing tool movable over a joint disposed between adjacent board sections, a hollow rectangular body having a top wall and an outlet adjacent to a trailing wall, the trailing wall having a flexible portion for the trailing wall and extending from end to end of the body, a flexible trailing bar adapted to contact the surfaces of the board sections disposed on either side of the joint formed by the sections, means connecting the bar to the flexible wall portion, means connecting the ends of the bar to the body, the top wall having an opening therein, the flexible portion for the trailing wall having an extension covering the opening, means including an electric motor for feeding mastic to the body interior under pressure, a switch connecting the motor with a source of current, and means actuated by the bulging of the flexible extension covering the opening for opening the switch and stopping the motor, the bulging being due to too great a quantity of mastic being received in the body.

2. In a finishing tool, a hollow body for receiving a mastic under pressure, the body having an outlet for depositing mastic on a wall-board surface, a flexible member forming a portion of the hollow body, means for feeding mastic to the interior of the body under pressure and including an electric motor, the flexible member bein distended when too large a quantity of mastic is received in the body, a switch for connecting the motor with a source of current, and means actuated by the flexible member when distended for opening the switch and stopping the motor, said last-named means permitting the flexible member to distend to an appreciable extent before opening the switch, and including adjustable means for applying a desired yielding pressure against the flexible member which must be overcome before the member will distend sufficiently to open the switch.

3. In a finishing tool, a hollow body for receiving mastic under pressure and having an outlet opening, an elongated semi-flexible bar constituting one side of the opening, means anchoring the ends of the bar to the body, a flexible wall forming a part of the hollow body and having an edge disposed near the bar, clips secured to the edge of the flexible wall and being removably secured to the bar, and adjustable means for moving at least one of the clips disposed intermediate the ends of the bar for flexing the bar into the desired curve.

4. In a finishing tool, a hollow elongated body for receiving mastic under pressure and having an elongated outlet opening, an elongated semiflexible bar constituting one side of the opening and having its ends secured to the body, a flexible member forming a part of the body Wall and having an edge disposed adjacent to the bar, a plurality of clips secured to the edge of the flexible member and removably secured to the bar, and adjustable means for moving a clip near the center of the bar for flexing the bar to form the desired curvature therein.

5. In a finishing tool, a hollow elongated body for receiving mastic under pressure and having an elongated outlet opening, an elongated semiiii flexible bar constituting one side of the opening, the bar having a plurality of selective troweling edges, means removably anchoring the ends of the bar to the body, a flexible member forming a part of the body wall and having an edge disposed adjacent to the bar, a plurality of clips secured to the edge of the flexible member and removably secured to the bar with a troweling edge of the bar projecting beyond the clips, and adjustable means for moving a clip near the center of the bar for flexing the bar to form the desired curvature therein.

6. In a finishing tool, a hollow body for receiving a mastic under pressure and having an outlet opening, means including an electric motor for delivering mastic to the body interior under pressure, said body having a flexible wall portion subject to distention when the pressure of the mastic in the body interior exceeds a predetermined point, a terminal carried by the body, a lever pivoted to the body and carrying a terminal, said terminals being connected to a source of current and the motor, spring means for urging the lever for moving its terminal into contact with the other terminal, a member carried by the lever and contacting the flexible wall portion, the member being moved by the distending of the flexible wall for moving its terminal out of contact with the other terminal, whereby the circuit is broken to the motor.

'7. In a finishing tool; a hollow body for receiving mastic under pressure and having an outlet opening; an elongated semi-flexible bar con stituting one side of the opening; means anchor ing the ends of the bar to the body; a flexible wall forming a part of the hollow body and having an edge disposed near the bar; a plurality of aligned clips arranged along the length of the bar; each clip having upper and lower channels; the upper channels of the clips being removably clamped upon the marginal portion of said flexible wall edge, and the lower channels being removably clamped upon the bar.

8. In a finishing tool; a hollow body for receiving mastic under pressure and having an outlet opening; an elongated semi-flexible bar constituting one side of the opening; means anchoring the ends of the bar to the body; a flexible wall forming a part of the hollow body and having an edge disposed near the bar; a plurality of aligned clips arranged along the length of the bar; each clip having upper and lower channels; the upper channels of the clips being removably clamped upon the marginal portion of said flexible wall edge, and the lower channels being removably clamped upon the bar; an adjusting rod secured to one of the clips disposed intermediate of the ends of the bar; and adjustable means for moving the rod to flex the bar into a desired curve.

9. In a finishing tool; a hollow body for receiving mastic under pressure and having an outlet opening; an elongated semi-flexible bar constituting one side of the opening means anchoring the ends of the bar to the body; a flexible wall forming a part of the hollow body and having an edge disposed near the bar; a plurality of aligned clips arranged along the length of the bar; each clip having upper and lower channels; the upper channels of the clips being removably clamped upon the marginal portion of said flexible wall edge, and the lower channels being removably clamped upon the bar; an adjusting rod secured to one of the clips disposed intermediate of the ends of the bar; and adjustable means for moving the rod to flex the bar into a desired curve; the rod being vertically disposed and guided in an opening in the body; and the adjustable means for the rod including a lever mounted above the body for free access thereto.

10. In a finishing tool, a hollow body for receiving mastic under pressure and having an outlet opening, an elongated semi-flexible bar constituting one side of the opening, means anchoring the ends of the bar to the body, the intermediate portion of the bar being flexible under pressure, a flexible wall forming a part of the hollow body and having an edge disposed near the bar, clips secured to an edge of the flexible wall and being removably secured to the bar, and a baffle plate secured to the body and forming a partial closure over the outlet.

ROBERT G. AMES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,709,711 Dufiy Apr. 16, 1929 2,300,398 Ames Nov. 3, 1942 2,301,498 Ames Nov. 10, 1942 2,413,684 Ames Jan. '7, 1947 2,436,783 Ames Mar. 2, 1948 

